Title :
P2N-7 Wide Bandwidth SAW Chirp Filters with Improved Magnitude Response
Author :
Gong, Junjie ; Zhang, Yuxing ; Zhou, Xianwen ; Hartogh, Paul
Author_Institution :
Inst. of Acoust., Chinese Acad. of Sci., Beijing
Abstract :
Three wideband SAW chirp filters are reported. They are 1 GHz central frequency with 400 MHz bandwidth and 10 mus chirp duration, 1.5 GHz central frequency with 600 MHz bandwidth and 10 mus chirp duration, and 2 GHz central frequency with 800 MHz bandwidth and 6 mus chirp duration, respectively. With our regular design and fabrication, the passband has a 2~3 dB peaking at the high frequency end for these wide bandwidth chirp filters. To suppress the peaking, some extra grooves are inserted before the reflective gratings, which partially diffracts the acoustic wave at the peaking frequency. This method has been proven effective and has little degradation on other performances. A chirp transform spectrometer (CTS) based on the 400 MHz bandwidth chirp filters has been built and the spectrum output shows good compressed pulse
Keywords :
chirp modulation; surface acoustic wave delay lines; surface acoustic wave filters; ultrasonic delay lines; ultrasonic diffraction; 1 GHz; 1.5 GHz; 10 mus; 2 GHz; 400 MHz; 6 mus; 600 MHz; 800 MHz; CTS; acoustic wave diffraction; central frequency; chirp duration; chirp transform spectrometer; compressed pulse; magnitude response; peaking suppression; reflective gratings; wide bandwidth SAW chirp filters; Acoustic diffraction; Band pass filters; Bandwidth; Chirp; Diffraction gratings; Fabrication; Frequency; Passband; Surface acoustic waves; Wideband;
Conference_Titel :
Ultrasonics Symposium, 2006. IEEE
Conference_Location :
Vancouver, BC
Print_ISBN :
1-4244-0201-8
Electronic_ISBN :
1051-0117
DOI :
10.1109/ULTSYM.2006.478
